Pushbutton switch construction with safety set mechanism



A. A. Dl PILLA June 23, 1970 PUSHBUTTON SWITCH CONSTRUCTION WITH SAFETY SET MECHANISM 6 Sheets-Sheet 1 Filed Jan. 25, 1968 FIG-l 9r M 2 n4 8 C 7 OO 9 INVENTOR ANTHONY A. Di PILLA HIS ATTORNEYS A. A. Dl PILLA June 23, 1970 PUSHBUTTON SWITCH CONSTRUCTION WITH SAFETY SET MECHANISM Filed Jan. 25, 1968 6 sheets sheet 3 FIG-3 INVENTOR ANTHONY A. Di PILLA HIS ATTORNEYS A. A. DI PILLA June 23,v 1970 PUSHBUTTON SWITCH CONSTRUCTION WITH SAFETY SET MECHANISM Filed Jan. 25, 1968 6 Sheets-Sheet t FIG-9 FIG-8 9 w 4 2 34? 4 m w wq w 1 nn em?! 1 w. s O

INVENTOR ANTHONY A. DiPlLLA Z my HIS ATTORNEYS June 23, 1970 A. A. DI PILLA 3,517,148

PUSHBUTTON SWITCH CONSTRUCTION WITH SAFETY SET MECHANISM Filed Jan. 25; 1968 e Sheets-Sheet 5 FIG-l9 INVENTOR 287' ANTHONY A 0| PILLA Jun 23, 1970 0 PILLA 3,517,148

PUSHBUTTON SWITCH CONSTRUCTION WITH SAFETY SET MECHANISM Filed Jan. 25. 1988 6 Sheets-Sheet 6 270 -fi273 j W275 Li 11$] I [Q FIG-26 INVENTOR ANTHONY ADI PILLA HIS ATTORNEYS United States Patent US. Cl. 200-167 12 Claims ABSTRACT OF THE DISCLOSURE There is disclosed an illuminated pushbutton switch construction having a tubular casing that receives a pushbutton means at the upper casing end and has a lower switch means at the lower casing end. The pushbutton means is movable inward into the upper casing end by an initial pushing in action and thereafter movable upwardly by a release counterspring. action. This places the pushbutton means in operable locked condition to operate the switch means as often as desired. The pushbutton means may be removed from the casing by an upward movement, or by an upward, outward movement, followed by an inward, downward pushing action of the pushbutton means. Thereafter, the pushbutton means may be removed from the casing by an upward and outward removing action completely to remove the pushbutton from the casing. The pushbutton is prevented from actuating the switch means during the initial introduction of the pushbutton means into the casing, and the pushbutton can only operate the switch means after it has been released from the first pushing in action.

This application is a continuation-in-part of applicants copending application, Ser. No. 605,680, filed Dec. 29, 1966, now Pat. No. 3,396,602, for Actuating Mechanism in Pushbutton Switch Operating Devices.

One of the features of this invention includes a construction in which a pushbutton is introduced into the upper end of an axially directed casing and is then released to place the pushbutton means in operable locked condition to operate a switch means at the lower end of the casing.

Another feature of this invention includes a construction in which the pushbutton means cannot operate a switch means during the first or initial introduction of the pushbutton means into the casing and can operate the switch means as often as desired after the pushbutton means has been released from the first or initial pushed in position.

Another feature includes a construction whereby the pushbutton construction may be removed from the casing by a pulling out action alone, or by a pulling out action followed by a pushing in action.

Another feature of this invention includes a construction in which a plunger is provided at the lower end of the casing to actuate the switch means.

Other features of this invention are apparent from this description, the appended claimed subject matter, and/ or from the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of an embodiment of this invention including a casing with one form of a switch at one end of the casing and with a pushbutton means outside the other end of the casing.

FIG. 2 is a vertical cross section of FIG. 1 taken along the line 22 of FIG. 1.

FIG. 3 is a transverse vertical view of FIG. 2, taken on the line 3-3 of FIG. 2.

3,517,148 Patented June 23, 1970 FIG. 4 is a view similar to FIG. 2, but showing the pushbutton means partially inserted in the casing.

FIG. 5 is a view similar to FIG. 4, but showing the pushbutton means further pushed in by an initial pushing in action, that does not actuate a plunger to switch actuating position.

FIG. 6 is a view similar to FIG. 5 but showing the pushbutton means moved slightly outward from the position of FIG. 5, by released counter action, in a manner to place the pushbutton means in operable locked condition.

FIG. 7 is a view similar to FIG. 6, and showing the pushbutton means pushed in from the position of FIG. 6 to a position Where the plunger actuates the switch attached to the end of the casing.

FIG. 8 is a view similar to 'FIG. 6 and showing the pushbutton means subjected to an initial pulling out action upward preparatory to releasing the pushbutton means from the casing.

FIG. 9 is a view similar to FIG. 8, but showing the pushbutton means pushed in from the position of FIG. 8 to perform the second step in releasing the pushbutton from the casing.

FIG. 10 is a view similar to FIG. 9, but showing the pushbutton moved outwardly from the position of FIG. 9 by a released counter action, which permits the pushbutton means to be removed outwardly from the casing.

FIG. 11 is an exploded perspective view of the plunger actuating center member or safety cam.

FIG. 12 is a cross section taken along the line 12-12 of FIG. 11.

FIG. 13 is a diagrammatic upward view along line 1313 of FIG. 7.

FIG. 14 is a broken cross section along line 14-14 of FIG. 13.

FIG. 15 is an exploded perspective view of an illuminated pushbutton switch assembly embodying the present invention with parts in phantom.

'FIG. 16 is an exploded vertical cross-sectional view of the assembly of FIG. 15.

FIG. 17 is a vertical cross-sectional view of FIG. 15 in its initial step of being assembled.

FIG. 18 is a cross-sectional view similar to FIG. 17 but shown in its ready to operate assembled position.

FIG. 19 is a cross-section view similar to FIG. 18 but showing its position when operated from the position of FIG. 18.

FIG. 20 is a partial cross-section of a detail taken along line 20-20 of FIG. 18.

FIG. 21 is an enlarged partial cross-section of the motion translating portion and plunger portion in their respective positions when the operator actuating portion is separated from the base unit.

FIG. 22 is a partial cross-section similar to FIG. 21 but with the motion translating portion and plunger portion shown in the positions when the operator actuating portion is being inserted upon the base unit.

FIG. 23 is a partial cross-section similar to FIG. 22 but with the motion translating portion and plunger portion shown in the ready to operate position.

FIG. 24 is a partial cross-section of a detail taken along line 2424 of FIG. 22.

FIG. 25 is a top plan view of a detail of FIG. 24.

FIG. 26 is a top plan view of a detail of FIG. 21.

Certain words, which indicate direction, relative position, and the like, are sometimes used in this specification and in the claimed subject matter for the sake of brevity and clearness. However, it is to be understood that these words are used only in connection with the views in the drawings, and that in actual use the parts so described may have entirely different direction, relative 3 position, and the like. Examples of such words are vertical, horizontal, upper, lower, etc.

An embodiment of this invention may include an axially directed casing 20 which may be a tubular casing. The casing 20 may have an upper pushbutton means receiving first casing end 22 and a lower switch means receiving second casing end 24. A pushbutton means 26 is movable inward relatively to said first casing end 22 by an initial pushing in action, such as shown sequentially in FIGS. 4 and 5, and thereafter movable upwardly relative to said first casing end 22 by released counter action, or spring action, as shown sequentially in FIG. 6 with relation to FIG. 5 to place said pushbutton means in operable locked condition so that said pushbutton means 26 may thereafter be repeatedly pushed in to the position of FIG. 7 and released to the position of FIG. 6 to operate switch means 28 at the lower end 24 of the casing 20.

The pushbutton means 26 may be released and removed from the locked operable condition of FIGS. 6 and 7 by an initial pulling out action on said pushbutton means, as shown in FIG. 8, followed by a pushing in action on said pushbutton means 26, as shown in FIG. 9. Thereafter the pushbutton means 26 may be released and removed from the casing 20 as illustrated in FIGS. 10 and 2.

If desired the release and removal of the pushbutton means from the casing may include an upward and outward released counter action, or counter spring action, produced from the position of FIG. 9 to the position of FIG. 10. This may include the counter spring action of the compression springs of the lower lamp energizing contacts 32, and the counter spring action of the compression spring 34 of the plunger 36.

Switch means may be provided at the second casing end 24. Under certain conditions such means may be considered to be the lamp energizing contacts 32 and 38. Under certain other conditions, such switch means may be considered to be the plunger actuator actuatable switch means 28, which is secured to the second easing end 24, by means of bracket 40. Such plunger actuatable switch means 28 may have a switch actuator rod 42 which may be moved inward and outward to place the switch means 28 in actuated or unactuated condition, as is well known. Such actuator rod 42 may be movable into the switch 28 to place the switch 28 in actuated condition, as shown in FIG. 7, and may be released to move outwardly, to place the switch 28 in unactuated condition, as shown in FIG. 6.

The switch actuator rod 42 may be moved down to actuated condition of FIG. 7, or to unactuated condition as shown in FIG. 6 and other figures, by the upwardly spring biased plunger 36.

The construction is such that the pushbutton means 26 operates locking means, to be described, to lock said pushbutton means 26 in operable locked condition, as shown in FIG. 6, by an initial pushing in action, as shown in FIG. 5, followed by 21 released counter action or spring action which moves the pushbutton means 26 to the operable position shown in FIG. 6.

When the pushbutton 26 is in the operable condition shown in FIG. 6, it may be repeatedly operated or pushed in, to the position of FIG. 7, to cause the plunger 36 to move down and engage the switch actuator rod 42, to place the switch 28 in actuated condition. Thereafter, the pushbutton means 26 may be repeatedly released to return by released counter action or spring action to the position of FIG. 6 which places the switch 28 in unactuated condition because of the upward movement of the plunger 36 away from the rod 42. Thus pushbutton means 26 may be repeatedly moved downwardly to the position of FIG. 7 and be released to move upwardly to the position of FIG. 6 as many times as desired.

The pushbutton means 26 may be removed from the casing 26 by performing the operations sequentially shown in FIGS. 8, 9, l0, and 2. The pushbutton means is first pulled out to the position of FIG. 8, and such movement starts a pushbutton means releasing means so that the pushbutton 26 will be eventually removed from the casing 20 by sequentially following the steps of FIGS. 8, 9, l0, and 2. Thus, after the pushbutton means has been pulled out to the position of FIG. 8, it is then pushed in to the position of FIG. 9 and released. This may be followed by a released action of FIG. 10, where the pushbutton means 26 is released and is moved upwardly by counter action, such as by counter spring action produced for example first by the combined spring action of springs 30 and 34 followed by the single spring action of the spring 34 as more fully to be described.

When the pushbutton means 26 is initially pushed in to lock the pushbutton means 26 in the operating or operable condition of FIG. 6, as shown in the sequential positions of FIGS. 1-6, the plunger 36 is pevented from actuating the switch means 28 and its actuating rod 42. The downward travel of the plunger 36 is arrested, as shown in FIG. 5, so that the plunger lower end 44 cannot travel downwardly below the lower line 47 of the two datum plane lines 47 and 49, so that the plunger cannot accidentally actuate the switch means 28.

However, after the pushbutton means is released to the position of FIG. 6 so that the pushbutton means 26 is in operating or operable condition, the plunger 36 is permitted to operate the switch means 28 to actuated condition, as shown in FIG. 7, when the pushbutton means is again pushed down.

Thereafter, if the pushbutton means 26 is released to return to the condition of FIG. 6, the switch means 28 also returns to unactuated condition because the plunger end 44 rises above and out of contact wtih the uppermost position of actuating rod 42.

During any subsequent pushing in and releasing actions of the pushbutton means 26 between the positions of FIGS. 6 and 7 the plunger 36 is permitted to operate the switch means 28 to actuated and unactuated conditions as often as desired. This can continue until the pushbutton means 26 is removed by the sequential operations illustrated in FIGS. 8, 9, l0, and 2, as elsewhere described.

The details by which the above operations and actions are achieved will now be described.

THE PUSHBUTTON CONSTRUCTION MEANS The pushbutton means or pushbutton construction means 26 may include a lamp holder means 46 and a pushing member means or lens holder means 48 relatively movably connected together by a connecting and moving frame means 50 which imparts relative movements between the lamp holder means, the lens holder means, and other parts of the embodiment.

THE LAMP HOLDER MEANS The lamp holder means 46 includes an upper platelike section 52 and a lower plate-like section 54 which may be made of electrical insulating material and which may be permanently secured together during the assembly of the parts, as is apparent from other descriptions in this disclosure.

A plurality of electrically energized flange base lamps 56 may be removably mounted in the resilient insulating section 54 of the lamp holder means 46. The lamps 56 may have lamp flanges 57 which carry the upper lamp energizing contacts 38 which are relatively permanently frictionally mounted in the lamp holder 46. The lamps 56 may emit diflferently colored light to or through the lens holder means 48. The mounting and construction of such lamps 56, flanges 57 and contacts 38 form, of themselves, no part of this invention. They are now well known in connection wtih this type of embodiment and are therefore not further described in detail herein. These lamps 56, flanges 57 and contacts 38 move in unison with the lamp holder means 46. The lamp 56 may be removed downwardly from the section 54. If desired, the upper plate-like section 52 may have means to hold colored flexible light filters over the lamps 56 in a manner now well known. The filters may be removable upwardly from the section 52, while the flange based lamps 56 may be removable from the bottom of section 54, in a manner now well known.

The lamp holder means 46 also has a locking spring means 58 which may be made from two resilient wire members. Each wire member may be bent into a pair of downward U-shaped legs 60 connected together by a horizontal spring member 62. The legs 60 may also be respectively connected to downwardly directed inverted L-shaped wire ends 64 which are locked between the joining surfaces of sections 52 and 54 and are also held in grooves 66 in the lower section 54.

The legs 60 and the horizontal spring member 62 are resiliently horizontally movable together and have the normal unbiased position shown in FIG. 2 with the member 62 and the double slant portions 67 of the legs 60 extending horizontally out beyond the inner surface line 68, FIG. 2, of the casing 20. Such horizontal member 62 and the double slant portions 67 are moved inwardly when the pushoutton means 26 is pushed into the casing 20 as shown in other figures of the drawings.

The lamp holder means 46 also has a safety means or safety cam means 70, FIGS. 2, 11 and 12, which is located in a horizontal cam slot 72 in the lower section 54 of the lamp holder means 46. The slot 72 is covered by the upper section 52. The safety cam means 70 is used as part of the means for preventing the plunger 36 from actuating the switch means 28, as in FIG. 5, and as part of the means permitting the plunger 36- to operate the switch means 28, as in FIG. 7, as elsewhere more fully described.

The lamp holder means 46 also has outer openings 74 to receive and allow passage of outer connecting and moving frame members 76 for engagement with and actuation of the locking spring means horizontal member 62, etc. Such lamp holder means also has a central opening 78 to receive and allow passage of an inner connecting and moving frame member 80 which is part of the means for preventing the plunger 36 from actuating the switch means 28, as in FIG. 5, and as part of the means for permitting the plunger 36 to operate the switch means 28, as in FIG. 7, as elsewhere more fully described.

THE LENS HOLDER MEANS AND CONNECTING AND MOVING FRAME MEANS The lens holder means 48 is the pushing in and removing element of the pushbutton means 26. The connecting and moving frame means 50 connects and moves the lamp holder means 46 into and out of the casing 20, in response to the movement of the lens holder means 48 and other parts of the embodiment, as shown in the various figures of the drawings.

The lens holder means 48 includes a lens holder box 82 which may be locked and supported by the offset shoulders 84 on the outer frame members 76. Also, lens holder walls 86 may be carried by or be formed as enlargements of the outer frame members 76.

A colored lens 88 and a top lens '90 may be held by the lens holder means 48.

The colored lens 88 may rest on a recessed ledge 92 which is formed in opposite walls of the lens box 82. The colored lens 88 may be rectangular to fit closely adjacent the inner surfaces of the lens box 82 with opposite protrusions to fit in the ledge 92. Alternatively, the vertical edges 94 of the recessed ledge 92 may be extensions of the inner surfaces of the opposite walls 96 of the box 82, and the colored lens 88 may be rectangular with two edges engaging the enlargement walls 86 and two other edges engaging the inner surfaces of oposite walls 96.

The top lens may be rectangular with two wedgeshaped protrusions 98 locked in openings 100 in the enlargement walls 86.

The central or inner connecting and moving frame member 80 may be generally T-shaped, as seen in FIG. 2, with the ends of the horizontal part 102, flanged members 104, connected to outer frame members 76 so that the frame member 80 is carried by the outer frame members 76.

The central frame member 80 has a vertical flange 106 and an offset shoulder 108 which engages and disengages a lug or shoulder 110 on the safety cam means 70, FIGS. 2, 11 and 12 to produce the switch means 28 actuating action by plunger 36 in FIG. 7 and the switch means 28 ,non-actuating action by the plunger 36 in FIG. 5, as more fully elsewhere described.

THE CASING AND TERMINAL BLOCK The casing 20 may be a tubular metal casing which may be of rectangular or square cross section. Switch retaining clip means 112 at the bottom of casing 20 may include a plate 114, FIGS. 3 and 4, which is riveted to the inward casing flanges 116 by rivets 118. The plate 114 has a downward hook 120 and a downward resilient spring latch 122 to receive and secure the upper plate 124 of bracket 40 of the switch means 28.

A pair of lugs 126, FIG. 4, are also riveted to the flanges 116 and hold a plunger guiding ring 128 to receive the lower end of the plunger 36.

Square rods 131 may be initially welded to the sides of the casing 20 to preliminarily receive and locate a terminal block 130 of insulating material in the casing 20. The terminal block 130 is then secured in fixed position in casing 20 in any suitable manner, such as by tabs (not shown) above the rods 131 forming a part of the casing 20. Each tab is bent inwardly and received above a shoulder (not shown) formed in the block 130. The terminal block 130 carries upwardly biased terminal members or pins 132 which carry the lamp contacts 32 and are upwardly biased by compression springs 30. The upward travel of the terminal members 132 pass through rings 138 forming a part of terminal attaching clips 136 which extend upwardly through block 130. The rings 138 receive the lower ends of the spring 30 to electrically connect the terminal members 132 with the contacts 32.

The plunger 36 passes through the terminal block 130 and is upwardly biased by the compression spring which extends from the upper surface of lower flange 140 of spring receiving opening 142 to the upper plunger flange 144. A ring 145 is fixed near the lower end of the plunger 36. The upward travel of plunger 36 is limited by the ring 145 on plunger 36 engaging the lower surface of lower flange 140.

Stops 146 are formed in the casing 20 by forming openings 148 and bending the flanged stops 146 with their upper Slanting surfaces 150.

The switch means 28 may be any well known plunger operated switch having terminal connectors 152 to be connected into any desired circuit to be controlled by the switch means 28 by operation of actuating rod 42. The body of switch means 28 may be secured to the bracket 40 by any suitable fasteners 154.

A neutral connection for the lamps 56 is shown in FIGS. 13 and 14 which is applicable to all of the figures. However, other neutral connections may be used if desired.

A neutral connection metal plate 151 may be countersunk in the lower lamp base section 54, which plate 151 may surround opening 155 of the plate 151. The plate 151 may have branches 149 extending into notches 153 of the lamp openings 159 in the lamp base sections 52 and 54. The branches 149 have resilient upward neutral tongue contacts 161 which engage the usual neutral cylindrical metal sleeves 147 of the lamps 56.

One or more upwardly biased neutral contacts 32A may be supported on the supporting base 130 of the cas ing. These contacts 32A may each have an upward contact pin to engage the neutral plate 151 to provide illuminating contacts for the lamps 56 in combination with the live flange contacts 38. These contacts 32A may be generally the same in construction and action as the contacts 32. The neutral contacts 32A have not been illustrated in the other figures, since their addition in such figures would have an overcrowding effect.

OPERATION The pushbutton means or pushbutton construction means 26, in the condition of FIGS. 1-3, is moved downwardly to and past the position of FIG. 4. As the pushbutton means 26 is ushed down from the position of FIG. 4, the legs 60 temporarily arrest the downward movement of the lamp holder means past the upper edge of opening 22 of the casing 20. The lens holder means 48 continues to move downwardly moving central frame member 80 downwardly causing shoulder 108 to engage lug 110 of safety cam means 70. The outer frame members 76 move downwardly at the same time so that their lower bent portions 156 move centrally of the horizontal members 62 of the spring means 58. The lamp holder means 48 and lens holder means 46 then move downwardly together to the position shown in FIG. 5.

When the pushbutton means 26 has been pushed down to the position of FIG. 5, the shoulder 108 of central frame member 80 prevents the cam 70 from rotating clockwise causing the cam arms 158 to act on the plunger 36. This has caused the horizontal bridge member 157 of the plate-like section 52 of lamp holder means 46 to engage the stops or stop members 146 of casing 20. This has stopped downward movement of the lamp holder means 46. The horizontal spring members 62 have moved inwardly around the stops 146 by engagement with the slanting surfaces 150. Such spring members or means 62 have then sprung outwardly by their outward spring bias below the stops 146 to lock and arrest substantial upward movement of the lamp holder means 46 when the lens holder means 48 is released by the operator for upward movement of the lens holder means to the position of FIG. 6.

Also, during the downward pushing action from FIG. 4 to FIG. 5, the plunger 36 has been pushed down by the cam arms 158 of the safety cam means 70 so that the lower end 44 of the plunger 36 is stopped at datum line 47 out of actuating switch contact with switch rod 42. The plunger spring has been further compressed. If it is desired to have slight contact between the plungers 36 and 42 at this time the movement of plunger 42 should be insufficient to actuate switch means 28 to actuated condition.

Also, during the downward movement from FIG. 4 to FIG. 5, the lower energizing lamp contacts 32 have been pushed down by the upper lamp contacts 38 and the springs 30 have been further compressed.

After the parts have been pushed down by the downward movement between FIGS. 4 and 5, the operator releases the lens holder means 48 so that there is a limited upward movement of some of the parts to the positions of FIG. 6. The lamp holder means 46 remains locked in FIG. 6. From these positions of FIG. 6 the lens holder means 48 may be repeatedly pushed down to the position of FIG. 7 repeatedly to actuate and deactuate the switch rod 44 and the switch means 28.

When the operator releases the lens holder means from the positions of FIG. to the positions of FIG. 6, the lens holder means 48 and the lamp holder means 46 move up by the reaction of plunger compression spring 34 and contact compression springs The lamp holder means 46 is arrested in its upward travel by engagement of horizontal members 62 with the lower surface of stops 146. The lens holder means 48 continues to rise slightly due to the upward force applied to the cam arms 158 by the plunger compression spring 34 via the plunger 36. This further movement of the lens holder means 48 is limited by engagement of the upper plunger flange 144 with the lower surface of the lamp holder means 46. The safety cam is rotated clockwise about the pivot portion 160 and into opening 72 against the action of compression spring 166 removing the lug 110 of cam 70 from engagement with the shoulder 108 of central frame member 80. During this pivot action of cam 70 about pivot portion 160, which is received in a groove in the lower section 54 of the lamp holder means 46, the curved surfaces 162 of cam arms 158 move along the lower surface 164 of plate section 52 of the lamp holder means 46. The lower end of spring 166 rests on a lug 168 at the bottom of opening 72 and the upper end of spring 166 is held by lug 170 on cam 70.

It is apparent that the lower end of frame member will be out of engagement with the plunger 36 at the time lug 110 moves away from engagement with the shoulder 108 of member 80. This additional movement of the lens holder means 48 causes the bent portions 156 of the outer frame members 76 to engage the horizontal members 62 deflecting the outer frame members 76 a slight amount. This creates a force tending to move the lens holder means 48 toward the plunger 36. This force comes into play as the lug 110 is pivoted out of engagement with shoulder 108 to cause the lens holder means 48 to move toward the plunger 36. The shoulder 108 of frame member 80 is then positioned relative to the cam 70 so that movement of the plunger 36 toward the lower end 24 of the casing 20 in response to movement of the frame member 80 does not permit the cam 70 to rotate counterclockwise to permit the lug 110 of the cam 70 to be engaged by the shoulder 108 of member 80. When the plunger 36 is moved away from the cam 70, the cam 70 is urged counterclockwise by the spring 166 causing the lug 110 to be placed in sliding engagement with the edge of member 80 about the shoulder 108.

The lens holder means 48, FIG. 6, is therefore held in readiness to be repeatedly pushed down and released between the positions of FIGS. 6 and 7.

When the lens holder 48 is pushed down, as in FIG. 7, such lens holder 48 and plunger 36 are no longer arrested, as in FIG. 5, but are allowed to continue down to actuate the switch plunger rod 42 because the safety cam 70, in the position of FIG. 6, no longer can arrest the shoulder 108 of frame member 80. This permits the frame member 80 to push down the plunger 36 to the switch means 28 actuating position of FIG. 7. During this time the lamp holder means 48, and its sections 52 and 54, are held in the position of FIGS. 6 and 7 by the compression springs 30 and lamp contacts 32 and 38 and by the horizontal members 62 and stop lugs 146.

Removal of the pushbutton means 26 from the casing 20 is accomplished by the sequences shown in FIGS. 8, 9 and 10.

The lens holder means 48 of the pushbutton means 26 is first pulled upwardly and outwardly to the position of FIG. 8 from a previous position of FIG. 6. If desired, suitable fingernail grooves 172, FIG. 2, or the like may be provided in lens for initial pulling out action.

The upward pulling action is limited by the lower bent portions 156 of the outer frame member 76 acting on the upper horizontal bridge members of the arrested lamp holder means 48. Then the lens holder means 48 is then pushed downwardly to the position of FIG. 9. This downward movement is arrested by the stops or stop lugs 174 of frame members 76 which engage the horizontal members 62. The members 62 are arrested in their slight downward travel when the upper section 52 of the lamp holder means 46 engages the stops or stop lugs 146, as previously described. The stop lugs 174 are positioned on the frame members 76 so this downward movement of the lens holder means 48 is not sufficient to cause the plunger 36 to be moved a distance great enough to actuate the switch 28. Upon removal of the force providing this downward movement the lens holder-means 48 with the lamp holder means 46 are released from its locking relationship with the casing 20 and can be pulled upwardly out of casing 20, as shown in FIG. 10.

This removal action of FIGS. 8, 9 and is accomplished because when the lens holder means 48 is initially pulled up, as in FIG. 8, the lower bent portion 156 of the frame member 76 is withdrawn from its inward position relative to horizontal member 62 of FIG. 6. Then when lens holder 48 is pushed down, as in FIG. 9, the bent portion 156 moves outwardly of horizontal member 62. The locking spring means 58 are flexed inwardly as the stop lugs 174 are moved into engagement with the horizontal members 62 positioning the horizontal members 62 so they clear the stop lugs 146 upon subsequent upward movement of the lamp holder means 46.

The subsequent upward movement of the lamp holder means 48 occurs when the force causing the downward movement is removed allowing the upward reaction force of plunger compression spring 34 and upward pushing action of plunger 36 on the lower section 54 of the lamp holder means 46 together with the spring action of springs 30 to position the horizontal members 62 above the stop lugs 146. Additionally the spring action of spring 166 causes cam 70 to rock counterclockwise and cause cam arms 158 to further urge upward movement of the lamp holder means 46 along with the lens holder means 4 8. It will be noted that the inward flexure of the horizontal members 62 provides reaction forces which act on the bent portions 156 of the frame members 76 as the lamp holder means 46 and lens holder 48 are moved upwardly to cause a slight separation movement of the lamp holder means 46 and the lens holder means 48 as shown in FIG. 10.

The entire pushbutton means 26 can thereafter be removed from the casing to the position of FIGS. 1 and .2. Thus, upon removal from the casing 20 the lens holder means 48 and the lamp holder means 46 are positioned relative to one another so they can be again inserted in the casing without any special positioning of the parts by the user.

FIGS. 15 and 16 show another embodiment of a switch operating mechanism of modular design constructed in accordance with the principles of this invention. The actuating elements for the mechanism are mounted for movement relative to a casing 246 and its end opening or aperture means 248, and comprise an operator actuated portion or pushbutton construction means A and a motion translating unit B. The unit B includes a motion translating portion or subassembly 281 and a plunger portion or subassembly 276. With the motion translating unit B in a ready to operate position the portion 281 is acted on by the actuator rod 216 of unit A for moving the plunger portion 276 to operate a switch unit C carried at the end of a casing 246. The switching apparatus and contacts of the switch unit C are of conventional design and will not be described in detail inasmuch as any suitable electric switch may be utilized. A bulb or lamp mount 228 is carried by the operator actuated portion A to facilitate bulb replacement. The lamp mount has electric power applied to it via a terminal block 270 positioned between the switch mounting end of casing 246 and the lamp mount 228.

The operator actuated portion or pushbutton construction means A includes a frame 211 with opposed side walls 204 and 206 each having an inwardly bent top flange. This frame 211 is a pushing member means 211 that is relatively movably and unitarily secured together to a lamp holder means 228. A lens holder box 202 (details not shown) is positioned between the opposed side walls 204 and 206. A translucent or transparent lens 210 covers the upper end of the lens holder box 202 and is 10 positioned between the upper end of the box 202 and the top flanges of side walls 204 and 206. The switch actuating mechanism is operated by pushing on the lens 210 when the portion A is mounted in the casing 246.

The frame or pushing member means 211 includes a transverse member (not shown) which extends between the two walls 204 and 206. The box 202 is thus held in place between the lens 210 and the transverse member (not shown). A pair of guide legs 212 and 214 having an L-shaped cross section extend downwardly from side walls 204 and 206, respectively, and may be formed as an integral part of the frame 211. An actuator rod 216 is included in the operator actuating portion A and extends centrally downwardly beyond the lens box holder 202. Rod 216 may be conveniently attached to the transverse member (not shown) extending between the walls 204 and 206 or may be formed as an integral part of the transverse member. The rod 216 is a substantially flat elongated strip of generally rectangular cross section having its major axis aligned with the major axis of the frame 211. As shown in FIG. 22, the edges of the rod 216 provide camming surfaces which at the lower portion of actuator rod 216 vary in accordance with the tapered and outwardly extending projections 218 and 220 and neckdowned portion of the rod 216 providing depressions 222 and 224 between the projections 218 and 220 and two outwardly extending projections 223 and 225 at the end of the rod 216. The end of the rod 216 provides an abutment surface 226.

The lamp holder means or bulb mount 228 is carried by the operator actuated portion A and has a plurality of spaced bulbs 230, which are secured to the mount 228 as by screw threads or bayonet sockets (not shown) and which have bulb contacts 231 on the undersurface of the mount 228. As is apparent from FIGS. 17-19, the lens holder means or box 202 has recesses for the bulbs 230 to permit the pushing member means or frame 211 to be moved relative to the lamp holder means or bulb mount 228 without touching the bulbs 230. The bulb mount 228 has a pair of L-shaped openings 232 and 234 (FIG. 15) through which the button guides 212 and 214 are reciprocally disposed. The center of the bulb mount 228 has a rectangular opening 236 through which the lower portion of the rectangular rod 216 passes and is reciprocated by movement of the frame 211. The rectangular opening 236 extends through a central boss 238 on the bottom of the bulb mount 228, which boss terminates in an abutment surface 240 for a purpose to be described hereinafter.

A centrally located bore disposed along the major axis of the rectangular bulb mount 228 and transverse to the opening 236 intersects .the opening 236 so that such bore is divided into two bores which receive spring biased latches 242 and 244, respectively. The latches 242 and 244 may be of any conventional design having an inner cam follower portion 242C (244C) normally biased toward the opening 236 by a coil spring 242$ (2448) surrounding the shaft of an outer latching element 242E (244E). As is shown in FIG. 22, the coil spring 2428 (2448) is mounted in compression between the apertured stud at the bore end and the inner cam 242C (244C). Only apertured stud 242P is shown in FIG. 22. The inner cam followers 242C and 244C cooperate with the camming surfaces defined by the edges of the actuator rod 216 to control the position of the outer latching elements 242E and 244E. The outer latching elements 242E and 244E extend through the bore end and protrude through apertured studs thereat to the exterior of the bulb mount 228 when cam followers 242C and 244C engage the cam surfaces defined by the depressions 222 and 224 at the end portion of rod 216 ash shown in FIG. 16 and extend beyond the exterior of the bulb mount 228 when the cam followers 242C and 244C engage the cam surfaces presented by the portion of rod 216 above the projections 218 and 220.

The hollow rectangular housing or casing 246 has an upper peripheral flange 248 for panel mounting purposes 11 and a pair of lower side walls 250 and 252. The lower side. walls 250 and 252 are integral extensions of the upper side walls defining the housing 246 and such upper side walls have aligned openings 247 which receive the latching elements 242E and 244E of the bulb mount 228. The bottom end portions of side walls 250 and 252 are bent inwardly toward each other for attachment to a switch unit mount. The switch unit mount includes an upper flat plate 254, centrally apertured to receive the annular collar 256 of a guide bushing 258 axially alignable with the central aperture in a lower clamping plate 260, which is deformed downwardly in its central portion. The bent ends of side walls 250 and 252 are disposed between the upper and lower plates 254 and 260, all of which are secured as by rivets 262. One edge of upper plate 254 has a C-shaped clamp 264 depending therefrom while its opposite edge has a pair of C-shaped clamps 266 depending therefrom. With such an arrangement the switch C is merely snapped into assembled relationship between the clamps 264 and 266.

As is illustrated in FIG. 16, the operator actuated portion or pushbutton construction means A is inserted into the top opening of casing 246. A stop in the form of a tab 207 bent inwardly from a corner of the casing 246 is engaged by the edge of the side wall 206 of frame 211 when the operator actuated portion is inserted or actuated after insertion to limit inward travel of the operator actuated portion A. The side walls 204 and 206 are similar in that the rear portion as shown in FIG. 15 is narrowerthan the forward portion. The tab 207 therefore serves to orient the operator actuated portion A to the casing. Thus, it can not be inserted in the casing unless side wall 206 is positioned to engage tab 207. The bottom edge of the bulb mount 228 rests on stops 249 formed on the interior of the casing just below the side openings 247. A second set of similarly formed stops 268 define a support for an electric power connecting block 270 positioned to cooperate with the bulbs 230 in the bulb mount 228. A plurality of spring biased contacts 271, one for each bulb contact 231, project from the upper surface of the block 270 into engagement with the respective contacts 231. Each contact 271 has a terminal lug 272 projecting from the lower surface of the block 270 and being adapted to electrical connection to a power source in conjunction with the switch C for control thereby. The block 270, which may be made of any suitable dielectric material has a central bore 273 the lower portion of which is reduced in diameter by an annular boss 274.

The motion translating unit B is shown in detail in FIGS. 21-23 and includes the motion translating portion 281 and the plunger portion 276. The plunger portion 276 of unit B includes a reciprocable housing in the form of a tubular member 304 closed at one end for contact with the switch unit C with a slotted opening at the other end for receiving the motion translating portion 281. Two inwardly directed flanges 205 define a portion of the slotted opening. A top view of the plunger portion 276 is shown in FIG. 26. In the embodiment shown, the closed end of the tubular member 304 is formed by a plug 278 attached to the tubular member 304 in some convenient manner such as spot welding. The closed end could, also be made as an integral part of the tubular member 304. The closed end 278 of the plunger portion 276 extends through the guide bushing 258 at switch unit C end of the device. A snap ring 279 positioned in a peripheral groove in the plug 27 8 forming the closed end of the tubular member 304 engages the bushing 258 to limit upward movement of the plunger portion 276. The plunger portion is urged upwardly by a spring 275 held in compression between the annular boss 274 on terminal block 270 and an annular flange 277 presented at the upper end of the tubular member 304. While the snap ring 279 is large enough in diameter to engage the guide bushing 258, it is small enough to clear the opening in the lower plate mounting 260 to permit movement therethrough during switch actuation. The spring 275 being in compression between the annular flange 277 on the top of the tubular member 304 and the annular boss 274 formed in block 270 causes the block 270 to be biased in position against the stops 268 and when compressed further by movement of the plunger portion 276 outwardly from the switch mounting end of casing 246 provides the needed return force for the plunger portion 276.

The motion translating portion 281 of the motion translating unit B defines a safety means for preventing actuation of the switch C during initial insertion of the unit A into the casing 246 as will be apparent hereinafter and has a motion translating bar 285 for engagement with the rod 216 of the operator actuated portion A. A lower rod 282 formed as an integral part of bar 285 is positioned to reciprocably slide in a blind bore 280 1ongitu dinally disposed in the plug 278 and offset from the longitudinal axis thereof. The bore 280 defines the axis upon which the motion translating portion 281 reciprocates. A portion of the rod 282 extends upwardly from the bore 280. A coil spring 283 is mounted in compression between a washer 284 carried on the rod 282 and the lower end of the motion translating bar 285. The motion translating bar 285 has a generally rectangular outline with a curved outer wall 286 conforming to the curvature of the tubular member 304 to facilitate reciprocation therein. The top of motion translating bar 285 is a perpendicular flange 287, the free edge of which is similarly curved. On the surface opposite the curved wall 286, the motion translating bar 285 has a rectangular notch intermediate its lower end and top flange 287; the notch is defined by top and bottom shoulders providing abutments 288 and 289, respectively, spaced from each other by a vertical wall 290.

The abutment positioning means may be a slider 291 made of any suitable material having good bearing characteristics, such as nylon, which is positioned within the plunger portion 276 for movement between the abutments 288 and 289. The slider 291 has a generally H- shaped cross-section formed by a pair of side walls 292 and 293 joined at center wall 294. The side walls 292 and 293 have flat inner surfaces and arcuate outer surfaces conforming to the curvature of the tubular member 304 of the plunger portion 276. As is shown in FIG. 25, the top of slider 291 has a cross piece abutment 295 extending between the top of the two side walls 292 and 293 in a direction from the center wall 294 toward the periphery of the H-shaped slider. This abutment 295 would appear as a hemisphere in cross section if extended to such periphery, however, the extension terminates short of the periphery and its dimension is such as to conform to the dimension of notch shoulders or abutments 288 and 289. With such an arrangement, the slider 291 is slidable on the motion translating bar 285 with its center wall 294 engaging the flat wall portion of bar 285 and with its abutment 295 alternately engaging the shoulders or abutments 288 and 289. The slider center wall 294 is spaced slightly from the top abutment 295 to form a transverse slot. The opposite edges of top abutment 295 and center wall 294 are sloped to define a top cam surface 296 and a lower rest surface 297, respectively.

As illustrated in FIG. 24, one side of the H-shaped slider 291 straddles the adjacent portion of the motion translating bar 285, while the other side provides a slot through which a lever 298 considered a part of the plunger portion of the motion translating unit B extends. The lever 298 is made of a flat elongated strip having its upper end bent inwardly toward the slider 291 and bar 285 and terminating in a rounded end 299 which cooperates with the slider rest 297 and the slider cam 296 and provides an abutment for the plunger portion which cooperates with abutment 288 of the motion translating portion 281. The lower end of the lever 298 has a fulcrum member 300 resting on the top surface of plug 278 and terminates in a bifurcated ledge 302 engaging 13 the undersurface of the washer 284. The bifurcated ledge 302 extends at an acute angle with the main strip of lever 298 so that under the bias of the coil spring 283 the lever 298 is normally biased counterclockwise about the fulcrum 300 as viewed in FIG. 21; thus, the upper lever end 299 is always biased toward the bar 285 and slider 291 and is therefore positioned in accordance with the surfaces and abutments presented by the bar 85 and slider bar 291.

OPERATION In accordance with the present invention, replacement of bulbs 230 in the bulb mount 228 is accomplished without special tools or the need for skilled mechanics and the operator actuated portion A is easily reassembled in the casing 246 of the base unit B without causing actuation of the switch unit C.

Details regarding the positions of the parts of the motion translating unit B prior to removal of the operator actuated unit A are shown in FIG. 23. The switch actuating mechanism is then in a ready to operate position. As shown in FIG. 20, the opening 236 in the bulb mount 228 is narrower than the width of the flange 287 of motion translating bar 285 so that bulb mount 228 provides a means limiting the movement of the motion translating portion 281 outwardly from the plunger portion 276 in response to the force supplied by spring 283 when the switch actuating mechanism is in the ready to operate position. The spring 275 has, of course, acted to draw the snap ring 277 carried by the plug 278 into contact with the bushing 258 secured to casing 246. The portion of actuator rod 216 above and adjacent projection 218 (220) is then in contact with the cam follower 242C (244C) to keep the operator actuated unit A in place with the abutment surface 226 of rod 216 adjacent the upper surface of flange 287. Any actuating movement of rod 216 downwardly is then translated directly to the plunger portion of the motion translating unit B via the motion translating portion 281 since the abutment 288 provided by portion 281 is in motion translating relationship with the abutment provided by the end 299 of lever 298 forming a part of plunger portion 276 thus providing a direct mechanical coupling between the motion translating portion 281 and the plunger portion 276 of unit B upon actuation of the operator actuated portion A.

To replace the bulbs 230 in the bulb mount 228, an upward force, as by pulling on the flanges of the lens 210 of the operator actuated portion A, is needed to cause upward movement of the actuator rod 216 from the position shown in FIG. 18 due to the frictional engagement of the inner cam follower portion 242C (244C) with the upper surface of projection 218 (220). Upward movement of rod 216 causes the innner cam follower portion 242C (244C) of latch 242 (244) to move in response to the cam surface presented by the projection 218 (220) on rod 216 and then in response to the surface presented by the depression 222 (224). With the cam follower portion 242C (244C) urged into contact with the edge of rod 216 at the depression 222 (224), the outer latching elements 242E (244E) are withdrawn from locking engagement with the side opening 247 in casing 246. The projection 223 (225) acts as a stop preventing further movement of rod 216 relative to the bulb mount 228 thus allowing the operator actuated portion A and the bulb mount 228 to be removed as a single unit from the casing 246 as shown in FIG. 16. As can be seen in FIG. 16, the bulbs 230 are then accessible for replacement.

Upon removal of the operator actuated portion A and the bulb mount 228 from the casing 246 the motion translating unit B assumes the position shown in FIG. 16 and FIG. 21. The position of the housing of the plunger portion 276 of unit B remains unchanged. Removal of the means for restricting outward movement of the motion translating portion 281 allows the motion translating bar 285 to move outwardly from the plunger portion 276. This outward movement of bar 285 causes the abutment 289 to engage the cross piece abutment 295 of the slider 291 causing the slider 291 and the motion translating bar 285 to move together until the slider 291 engages the flanges 205 at the upper end of the tubular member 304 to terminate the outward movement of bar 285. Slider 291 is thus moved relative to and in contact with the lever 298 of the plunger portion 276 causing the end 299 of lever 298 to be moved outwardly in accordance with the cam surface presented by slider 291. The end 299 of lever 298 is positioned in the transverse slot in slider 291 present just below the abutment 295 upon termination of the movement of slider 291 and portion 281 by the stop provided by flanges 205 at the slotted end of the tubular member 304.

To assemble the switch mechanism for operation the operator actuated portion A positioned as shown in FIG. 16 is inserted in the casing 246 and an inwardly directed force applied tothe lens 210 whereupon the bulb mount 228 comes to rest on the housing stops 249; as is illustrated in FIG. 17. When the bulb mount 228 seats on the housing stops 249, the latches 242 and 244 are aligned with the housing openings 247. The boss 238 on the bulb mount 228 engages the flange 287 on the bar 285 of the motion translating portion 281 to displace the motion translating portion 281 a short distance relative to the plunger portion 276. The continued application of the inserting force effects continued downward movement of the rod 216 relative to the bulb mount 228 and the inner cam portions 242C and 244C of the latches 242 and 244. The latch cams 242C and 244C are displaced by the slopes presented by the projections 218 and 220 above the rod depressions 222 and 224, respectively, causing the latching elements 244 and 242 to be displaced outwardly through the housing slots 247. The portion of rod 216 above the projections 218 and 220 is wide enough to keep the latching elements 242 and 244 in the housing slots 247. Thus, the bulb mount 228 is latched to the casing 246 but the rod 216 may be depressed relative to the bulb mount 228. The inserting force is continued on the lens 210 causing further downward movement of rod 216 which via its abutment surface 226 acts on the flange 287 of motion translating bar 285 causing further movement of bar 285 against the bias of its coil spring 283 and relative to the plunger portion 276. Such movement of the bar 285 causes the spring 283 to be compressed. Prior to movement of the bar 285 the upper end 299 of lever 298 is in contact with the slider 291 at the transverse slot below the abutment 295 as shown in FIG. 21. Such contact of lever 298 with the slider 291 causes the bar 285 to move relative to the slider 291 until the abutment 288 of bar 285 is brought into engagement with the upper surface of the cross piece 295 of slider 291. The bar 285 and slider 291 then move downward as a unit causing the upper end 299 of lever 298 to be positioned outwardly along the cam surface 296. The upper end 299 of lever 298 is thus displaced relative to bar 285 and slider 291 to a point above the slider 291 and the abutment 288 as the bar 285 and slider 291 are moved to the limit of their unitary downward movement. The downward movement of rod 216 and therefore bar 285 and slider 291 is limited by the stop 207 provided for the operator actuated portion. The edge of side wall 206 engages the tab 207 to stop the inward movement of the operator actuated portion. The position of the motion translating portion 281 relative to the plunger portion 276 upon termination of the downward movement of the rod 216 is shown in FIG. 17 and FIG. 22. As has been mentioned, the force required to compress spring 283 is less than that required to compress spring 275 so there is no displacement of the plunger portion 276 due to the force used for the initial insertion of the operator actuated portion A into the casing 246 and its engagement with and the limited displacement of the motion translating portion 281 via the rod 216 as has been described.

Upon release of the inserting force, the energy stored in the compressed spring 283 moves the bar 285 upwardly from its position in FIG. 2 to the position in PM. 23 where the top flange 287 engages the lower end of boss 238. The rod 216 is also carried upward to the position shown in FIG. 18 and FIG. 23. During this limited upward movement of bar 285 the bar 285 moves relative to the slider 291 with the abutment shoulder 288 of bar 285 moving away from the slider abutment 295. As the bar 285 moves upward the notch in bar 285 between abutments 288 and 289 is presented to the upper end 299 of lever 298 which is normally biased counterclockwise about its fulcrum 300, allowing the lever end 299 to move into the notch of the plunger bar 285 for subsequent engagement with the abutment 288 of the bar 285 upon the application of an actuating force to the lens 210. The relative positions of the components for the actuating means are then as shown in FIGS. 18 and 23 and present a ready to actuate condition.

During the insertion of the operator actuated portion A and the lamp mount 228 in the casing 246 and its operation on the motion translation portion B as represented in the sequences from FIGS. 16 through 18 and from FIGS. 21 through 23, the switch unit C has not been actuated since the force applied via the operator actuated portion A only moves the motion translating bar 285 to compress spring 283 which requires less force to compress it than spring 275 which must be compressed if the plunger portion 276 is to move which is necessary to the operation of the switch unit C. A different situation is presented when the actuating means is in the ready to actuate position per FIGS. 1-8 and 23, When so positioned an actuating force applied to the lens 210 causes the actuator rod 216 to move downwardly with its abutment surface 226 in engagement with the top flange 287 of the motion translating bar 285 causing the bar 285 to move downwardly. Since the lever 298 then presents an abutment 299 for immediate engagement with the abutment 288 of the bar 285, downward movement of the bar 285 is transmitted directly to plunger portion 276 via its lever 298 and end plug 278 causing the spring 275- positioned between the flange 277 and boss 274 to be compressed. Accordingly, the entire actuating means moves as a unit downwardly causing the plug 278 of the motion transmitting portion 281 to operate the switch unit C. FIG. 19 shows the actuating means at the limit of its downward travel which is determined by the engagement of the operator actuated portion A with the stop tab 207 formed in the casing 246 for such purpose. Upon release of the actuating force on the lens 210, the entire actuating means is returned by the energy stored in the compressed coil spring 275 to its ready to actuate position as represented in FIGS. 18 and 23. Repeated operation of the switch unit C by depression of the lens 210 does not affect the motion translating relationship of the abutment 299 on lever 298 with the abutment 288 provided by the motion translating portion 281.

With the above arrangement, it is now apparent that actuating means comprising the operator actuated portion A and its associated bulb mount 228, the motion translating unit B having a motion translating portion 281 and plunger portion 276 with its housing and lever 298, which provides an operating abutment 299 for the plunger portion, permits removal of a portion of the switch assembly from the front of the panel in which it is mounted to permit bulb replacement or other repair and adjustment, and permits reassembly of the removal portion without any danger during such reassembly of operating the switch unit C secured to the end of the switch casing. The key to such operation lies in the motion translating unit B which can be viewed as having a first and second subassembly each providing a motion translating abutment. These abutments by an abutment positioning means are displaced relative to one another upon initial movement of the subassemblies toward one another with such displacement of the abutments preventing engagement of the abutments, the abutments being brought into position for engagement with one another upon subsequent limited movement of the two subassemblies in the opposite direction to permit the two subassemblies to operate as a motion translating unit. in response to relative movement of the subassemblies toward one another. The abutment positioning means is effective to displace the abutments from their motion translating position when the two subassemblies are moved away from each other in excess of subsequent limited movement referred to above. The initial movement of the two subassemblies toward one another occurs during insertion of the operator actuated portion A and the subsequent limited movement of the two subassemblies occurs upon release of the inserting force. Susequent movement of the subassemblies as an effective motion translating unit occurs when the operator actuated portion A has an operating force applied to it.

Many terms used in the above description, such as inward, upward, etc., are merely used to describe the particular drawing arrangements and are not to be deemed as actual arrangements. The location of the entire assembly need not be installed on a vertical axis but rather, in most installations, is aligned on a horizontal axis by mounting behind a console or panel board.

Inasmuch as the preferred embodiment of the present invention is subject to many modifications, variations and changes in detail, it is intended that all matter contained in the foregoing description or shown on the accompanying drawings shall be interpreted as illus trative and not in a limiting sense.

What is claimed is:

1. In combination:

a casing having a receiving casing aperture means;

switch means connected with said casing;

pushbutton construction means disposed in said casing aperture;

means for actuating and unactuating said switch means by actuating means of said pushbutton construction means being operatively associated with said switch means when said pushbutton construction means is disposed in a locked condition in said casing aperature means, said pushbutton construction means being movable inward relatively to said casing aperture means by a pushing in action;

locking and withdrawing means carried by said casing and said pushbutton construction means locking said pushbutton construction means in said switch means actuating and unactuating operable locked condition only by an initial locking pushing in action of said pushbutton construction means into said casing aperture means followed by a release of said pushbutton construction means, and to withdraw said pushbutton construction means from said operable locked condition by an initial pulling out action of said pushbutton construction means, said pushbutton construction means being inwardly actuatable and outwardly releasable for operating said switch means by said actuating means respectively to actuated switch means condition and to unactuated switch means condition while said pushbutton construction means is in said locked operable condition;

and safety means carried by said combination and being operatively associated with said actuating means, said safety means preventing said actuating means of said pushbutton construction means from operating said switch means to actuated condition during said initial locking pushing in action.

2. A combination according to claim 1 in which said pushbutton construction means includes a pushing member means that defiines said actuating means and a lamp holder means relatively movably and unitarily secured together, and in which said lamp holder means is locked to said casing by said initial lockingpushing in action of said pushing member means followed by a release of said pushing member means, and said pushing member means is pushable in and releasable out respectively to actuate and to unactuate said switch means While said lamp holder means is locked to said casing, and said safety means preventing said pushing member means from actuating said switch means to actuated condition during said initial pushing in action of said pushing member means.

3. A combination according to claim 2 in which said lamp holder means is unlocked from said casing by a withdrawing pullling out action of said pushing member means.

4. A combination according to claim 3 in which said pushing member means is a lens assembly means.

5. In combination:

a tubular casing having a receiving casing aperture means adjacent one end and a plunger guiding means adjacent the other end;

a switch means actuating plunger reciprocable in said plunger guiding means;

a switch means connected to said casing adjacent said other end and being actuatable by reciprocation of said plunger to switch means actuated condition and an unactuated condition;

a pushing member means and a lamp holder means relatively movably unitarily secured together as a pushbutton construction means and being insertable in and removable from said casing through said casing aperture means, said pushbutton construction means being disposed in said casing aperture means;

locking means carried by said casing and said pushbutton construction means locking said lamp holder means in locked condition in said casing only by an initial pushing in action of said pushing member means, followed by a releasing action of said pushin member means;

locking release means carried by said casing and said pushbutton construction means releasing said lamp holder means from said locked condition by a withdrawing pulling out action on said pushing member means;

a plunger reciprocating means connected to said pushing member means and being operatively associated with said plunger and reciprocating said plunger to switch means actuated condition by inward pushing in action on said pushing member means and reciprocating said plunger to switch means unactuated condition by release of said pushing member means While said lamp holder means is in locked condition;

and safety means carried by said combination and being operatively associated with said actuating means, said safety means preventing said plunger reciprocating means from reciprocating said plunger to switch means actuated condition during said initial pushing in action of said pushing member means.

6. A combination according to claim 5 in which said lamp holder means has spring biased members defining part of said locking means and locking said lamp holder means to said casing.

7. A combination according to claim 6 in which said casing has stationary members defining part of said locking means and engaging with said spring biased members to lock said lamp holder means to said casing.

8. In combination:

a casing having a receiving casing aperture means;

a switch means connected to said casing;

a pushing member means and a lamp holder means relatively movable unitarily secured together as a pushbutton construction means and being insertable in and removable from said casing through said casing through said casing aperture means, said pushbutton construction means being disposed in said aperture means, said switch means being actuatable to actuated condition and unactuated condition by pushing in action and release action on said pushing member means when said pushbutton construction means is in a locked condition in said casing aperture means, said pushing means being operatively associated with said switch means;

locking means carried by said casing and said pushbutton construction means and locking said lamp holder means in said locked condition in said casing only by an initial pushing in action of said pushing member means, followed by a releasing action of said pushing member means;

locking release means carried by said casing and said pushbutton construction means and releasing said lamp holder means from said locked condition by a withdrawing pulling out action on said pushing member means;

and safety means carried by said combination and being operatively associated with said pushing member means, said safety means preventing said pushing member means from actuating said switch means to switch means actuated condition during said initial pushing in action of said pushing member means.

9. A combination according to claim 8 in which said lamp holder means has a spring biased latch means defining part of said locking means, said casing having a latch receiving casing lock means defining part of said locking means and receiving said latch means to engage said casing lock means during said initial pushing in action, and said pushing member means having a cam means defining part of said locking release means and causing said latch means to disengage said casing lock means during said withdrawing pulling out action.

10. A combination according to claim 9 in which said spring biased latch means is inwardly spring biased and said cam means outwardly forces said latch means to engage said casing lock means.

11. A combination according to claim 10 in which said inward spring bias forces said latch means into disengagement from said casing lock means.

12. A combination according to claim 9 in which said spring biased latch means is outwardly biased into engagement with said casing lock means, and said cam means forces said latch means into disengagement from said casing lock means.

References Cited UNITED STATES PATENTS 2,904,662 9/1959 Spring 200159 3,090,949 5/ 1963 Hallerberg 200159 3,197,598 7/ 1965 Andersen et al.

3,249,705 5/1966 Amis et al.

3,267,245 8/1966 Vincent.

3,274,354 9/ 1966 Stevens.

H. O. JONES, Primary Examiner 

